French Onion Soup

• 4 tbsp butter
• 3 lb yellow onions (about 6 large), halved and thinly sliced
• 1 1/2 tsp kosher salt, plus more to taste
• 1 tsp sugar
• 3 cloves garlic, minced
• 2 tbsp all-purpose flour
• 3/4 cup dry white wine or dry sherry
• 8 cups beef broth
• 4 sprigs thyme
• 1 bay leaf
• 1 tbsp Worcestershire sauce
• 1 baguette, sliced 1/2 inch thick and toasted
• 3 cups (10 oz) grated Gruyère

1. 1Melt the butter in a large Dutch oven over medium heat. Add the onions, salt and sugar. Cover and cook 15 minutes, stirring occasionally, until the onions collapse.
2. 2Uncover and cook, stirring every few minutes and scraping the bottom, until the onions are deep golden brown and jammy, 50–60 minutes. If they stick, add a splash of water and scrape. That fond is flavor.
3. 3Add the garlic and cook 1 minute. Stir in the flour for 1 minute, then add the wine and scrape the pot clean.
4. 4Add the broth, thyme, bay leaf and Worcestershire. Simmer 20 minutes. Discard the herbs and season with salt and pepper.
5. 5Heat the broiler. Ladle the soup into oven-safe bowls set on a baking sheet. Top each with toasted baguette slices and a heap of Gruyère.
6. 6Broil until the cheese is bubbling and browned in spots, 2–4 minutes. Serve carefully; the bowls are very hot.

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